docs: def _get_config(self, unit, filename):
          """Get a ConfigParser object for parsing a unit's config file."""
          file_contents = unit.file_contents(filename)
  
          # NOTE(beisner):  by default, ConfigParser does not handle options
          # with no value, such as the flags used in the mysql my.cnf file.
          # https://bugs.python.org/issue7005
          config = configparser.ConfigParser(allow_no_value=True)
          config.readfp(io.StringIO(file_contents))
          return config